Tenter clips

ABSTRACT

A TENTER CLIP HAVING A BASE PLATE ON WHICH THE BORDER OF A STRIP TO BE CLIPPED IS PLACED AND A CLIP LEVER ROTATABLY PIVOTED TO THE CLIP BODY. THE CLIP LEVER CAN BE ROTATED IN SUCH A MANNER THAT THE LOWER END THEREOF IS BROUGHT INTO ABUTTING RELATIONSHIP TO THE BASE PLATE. THE LOWER END OF THE CLIP LEVER IS FORMED WITH A PLURALITY OF EDGES AT AN ANGULAR INTERVAL IN THE ROTATING DIRECTION OF THE LEVER AND AT DIFFERENT DISTANCES FROM THE FULCRUM POINT OF THE CLIP LEVER.

March 9, 1971 SABURO 3 ETAL 3,568,270

, TEN'I'ER CLIPS Filed Nov. 5, 1968 2 Sheets-Sheet 1 "FIG. I PRIOR ART 5-1 4 O I 3 5- 2 I 6'5 111 INVENTORS Sub-u Po Ida Yoshjo Koba ash l Mni'su l Hi -0o (3 ATTORNEYS March 9, 1971 s u o |DA El'AL 3,568,270

TENTER' CLIPS Fiied Nov. '5, 1968 v 2 Sheets-Sheet 2 F IG. 5 I FIG. 6

35 35 35-54) 31H 7 I0 I 35-4 7 7 25mm I 7 t T FIG. 1

CLIP ANGLE 0 ('C) n on a u a a L5 THICKNESS OF STRIP 't(MM) BY 27 05M? ATTORNEYS United States Patent Ofiice s. Cl. 24- -2 18 3 Claims ABSTRACT OF THE DISCLOSURE A tenter clip having a base plate on which the border of a strip to be clipped is placed and a clip lever rotatably pivoted to the clip body. The clip lever can be rotated in such a manner that the lower end thereof is brought into abutting relationship to the base plate. The lower end of the clip lever is formed with a plurality of edges at an angular interval in the rotating direction of the lever and at different distances from the fulcrum point of the clip lever.

SUMMARY OF THE INVENTION The present invention relates to a tenter clip construction adapted for tenten'ng machines or biaxial draft machines.

Tenter clips are widely used for stretching a strip in feeding motion, and have various structures and mechanisms for different purposes.

One structure of conventional tenter clips is illustrated in FIGS. 1 and 2. Along the borders of astrip 7 to be stretched there are arranged. two rails 1 on each of which a plurality of clips, one of which is shown in FIG. 1, are movably mounted with their clip stands 2 and linked to one another (not shown). The clip body 3 in the shape of an arch stands from the clip base 3, and has at its free end a pivot 4 serving as the fulcrum point for a clip lever '5. Thus the clip lever 5 is rotatable in the directions indicated with a bidirectional arrow. Provided on the base 3' is a liner 6 in view of the function of the clip or factors in working. The clip lever 5 has an arm 5-1, which extends above the fulcrum point 0 and is adapted to engage a cam member or the like (not shown) mounted on each end of the tenter. Upon engagement of the arm 5-1 with the cam member the clip lever 5 is brought into rotation about the fulcrum point 0 thereby lifting or lowering its lower arm 5-2 so that the fed strip 7 can be either caught by the clip or released therefrom.

Various constructions for the lower arm 5-2 have been devised for improving its clipping function. For example, the lower arm 5-2 is dimensioned in such a manner that its length is larger than the distance between the liner 6 and the clip lever 5, and the lower end 5-3 of the arm is shaped into a knife edge, as shown in FIG. 2. Further, to increase the friction between the strip 7 and the lower end 5-3 of the clip lever, the lower end can be corrugated.

However, in the prior tenter clip, the variation in thickness of the strip 7 inserted between the clip lever 5 and the liner 6 will necessitate the variation of the clip angle 0, which has an important influence upon the clipping function of the clip. The examinations showed that the clipping action for some strips, for example, polypropylene sheets might fail at a clip angle of more than 10. Thus the thickness of strips to be clipped may be limited. Though the clip angle 0 would be reduced by increasing the distance between the liner 6 and the fulcrum point 0, the moving tenter clip cannot be dimensioned so large taking tented. r- 9 all conditions into consideration. Therefore, such a tenter clip as described above cannot be. used for various purposes, for example, for clipping strips of relatively large thickness. i I

The principal object of the invention is to provide a tenter clip which can clip strips havinga wide range of thickness while keeping the advantage, of the above mentioned wedge action. I

Another object of the invention is to provide. a tenter clip simple in construction as well as in operation.

A further object of the invention is to provide a tenter clip small in size for its clipping performance.

In accordance with the invention, at the :end of a clip lever which is brought into abutting relationship to the base plate of a clip there. are formed a plurality of edges at an angular interval in the rotating direction of the clip lever, the distances between the. respective edges and the fulcrum point of the. clip lever being diiferent from one another.

The invention will be. more fully understood from the following description, taken in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a side. view of a pair of the above described prior tenter clips in stretching condition;

FIG. 2 is an enlarged side view of the tenter clip in FIG. 1;

FIG. 3 is a side view of a tenter clip according to the invention;

FIG. 4 is a perspective view of the tenter clip in FIG. 3

FIG. 5 is an enlarged view of a portion of FIG. 3 with a thin strip clipped;

FIG. 6 is a fragmentary view similar to FIG. 5 with a thick strip clipped; and

FIG. 7 is a graph indicating variation by clip angle with strip thickness.

DESCRIPTION OF A PREFERRED EMBODIMENT A tenter clip according to the invention is similar in the configuration of its clip body to the prior clip shown in FIG. 2, and differs from that in the form of the lower end of its clip lever and the distance relationship between the fulcrum point of the clip lever and the lower end in clipping position.

Referring now to FIGS. 3 and 4, a clip lever 35 with center of gravity lying below the fulcrum point 0 thereof (such selection of the center of gravity ensures a quick and secure initial clipping action) is pivoted to the body 33 of a clip in a similar manner to FIG. 2, and can be rotated counterclockwise about the fulcrum point 0 by means of a cam member (not shown) mounted on each end of the tenter.

The clip lever 35 is formed at its lower part with a touch member 35-4 consisting of one or more combshaped fingers which, when no strip exists on a liner 36 as a base plate, extend respectively into slits in the liner 36 and are dimensioned so as to follow the border of the strip even when the strip on the liner 36 comes deeply into the Clip.

The lower end 35-3 of the clip lever 35 is formed with two edges 35-3-a and 35-3-b which are arranged at an angular interval in the rotating direction of the clip lever 35 and at different distances from the fulcrum point 0, as shown in FIGS. 5 and 6. Those edges are rounded off so that a thin strip clipped may be prevented from being torn.

As mentioned above, in the prior tenter clips of this kind there is a fear that the clipping action theerof might become unreliable at clip angles above a certain value so that the thickness of strip to be clipped is limited. On the contrary, the structure of the clip according to the invention makes it possible to clip reliably strips of larger thickness than in the past.

The edges in FIGS. and 6 are dimensioned as follows:

The edge 35-3-11 can clip reliably strips having the thickness ranging from 0 to 0.7 mm. at a clip angle below a predetermined value while the other edge 35-3b ensures a reliable clipping action for strips having the thickness in the range from 0.7 to 1.5 mm. at a clip angle below another predetermined value.

The relation between the clip angle 0 and the thickness 1 of strips to be clipped is diagrammatically illustrated in FIG. 5, wherein the acting ranges of both edges are drawn with heavy curves. When no strip exists, the clip angle 0 of the edge 35-3-11 amounts to 4' while that of the edge 353b is equal to 3. With increase in the thickness of strips to be clipped both clip angles 6 of the edges 35-3-a and 353-b increase together. Up to t=0.7 mm. only the edge 35-3-a undertakes clipping action, because the other edge 35-342 does not act at clip angles below 10. At the thickness t=0.7 mm. both edges 35-3-a and 35-3-1) owing to their geometrical dimension exert clipping action upon strips. For strips having the thickness above t=0.7 mm., the edge 35-3-b undertakes clipping action while the edge 35-3-a is out of contact with the strips. Thus, the range of clipping can be extended through succession of clipping action by both edges 35-3-a and 35-3-b.

The clipping point of the clip lever on the liner 36 displaces in accordance with the thickness of strips to be clipped, but this does not matter to the function of the tenter clip on the whole.

In the embodiment illustrated, the liner 3 6 is of a fiat surface. However, a liner which has a slanting or curved surface for easy clipping can be used.

From the foregoing description it is apparent that at least one of edges formed at the end of the clip lever clips a strip between it and the base plate at an angular position of the clip lever corresponding to the thickness of the strip so that the strip can be clipped at a desirable clip angle selectively by at least one of those edges. Accordingly, the degree of freedom for adaptability of the tenter clip to a wide range of the thicknesses of strips to be clipped can be extended with the advantages of simple construction and operation of the tenter clips heretofore in use.

While the invention has been described in only one embodiment, it will be readily apparent that many modifications thereof may be made without departing from the spirit and scope of the invention.

What is claimed is:

1. A tenter clip for engagement of strip material com- 10 prising a clip body with a base plate having a front end with a flat surface on which the strip material is placed and a recess therein rearwardly of said flat surface, a clip lever rotatably supported on said body and having an outer portion with at least two angularly spaced engagement surfaces selectively engageable over the strip material on said flat surface and defining respective distinct engagement surface spacings above said plate for engagement for different thicknesses of strip material, said clip lever having a follower member portion engageable in the recess 2 to the rear of the edge of said strip material and providing an abutment edge for spacing the edge of the strip material in respect to said engagement surfaces.

2. A tenter clip, according to claim 1, wherein said engagement surfaces are rounded.

3. A tenter clip, according to claim 1, wherein said engage'rnent surfaces are separated by a recess in said lever, said follower member portion comprising an angled portion extending rearwardly of said lever into the recess.

References Cited DONALD A. GRIFFIN, Primary Examiner 40 US. or. X.R. 

